


detail your sin

by thorkidumpster



Category: Thor (Movies)
Genre: Alternate Universe - Human, Anal Sex, Bottom Thor, Butt Plugs, Loki is a shit, M/M, Neck Grabbing, Plot What Plot/Porn Without Plot, Twincest, bros being bros, but that's pretty much every thorki fic ever, light pregnancy kink talk
Language: English
Status: Completed
Published: 2017-04-16
Updated: 2017-04-16
Packaged: 2018-10-19 13:31:51
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 3,633
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/10640835
Author URL: https://archiveofourown.org/users/thorkidumpster/pseuds/thorkidumpster
Summary: Thor licks his dry lips, then licks them again. The plug inside him burns, but not as much as the humiliation that churns in his stomach at the thought of anyone finding out—his co-workers, his friends, his students…He’s a respected teacher at Shield High, well loved for his easy-going nature and tendency to forgo homework when the mood strikes him. He works out five times a week and volunteers at a food bank, always gives generously without strings, and loves when his brother fucks him in the ass and stuffs him with cum.





	

**Author's Note:**

> This was originally posted on tumblr! Check me out @ thorkidumpster.tumblr.com.
> 
> Also, thank you to the wonderful fourletterwordsstartingwithl for beta'ing this filth :) You're a doll!

* * *

 

Thor licks his dry lips, then licks them again. The plug inside him burns, but not as much as the humiliation that churns in his stomach at the thought of anyone finding out—his co-workers, his friends, his _students_ …

He’s a respected teacher at Shield High, well loved for his easy-going nature and tendency to forgo homework when the mood strikes him. He works out five times a week and volunteers at a food bank, always gives generously without strings, and loves when his brother fucks him in the ass and stuffs him with cum.

The final bell rings and Thor exhales long and slow, as though he were in the middle of a yoga stretch and not fighting back the halfie that’s been chubbing up for most of the day.

(When his kids asked why he hadn’t been bouncing around the room with his usual exuberance, he blushed red and said, “Leg day,” which made the football players in the room wince with sympathy.)

With shaking, but purposeful hands, Thor begins to pack up his desk as soon as the last student has walked out with a cheerful, “Have a nice weekend, Mister Odinson!” tossed over her shoulder.

Loki is waiting at home, he knows, probably lounging on the couch or eating all his junk food in the name of ‘getting rid’ of it because it’s awful for him. As though, of course, it weren’t equally as awful for Loki—but bring that point up and Loki gets shifty eyed, prickly. More that he wants to eat is so Thor can’t have it, because apparently Loki’s a four-year-old hiding in a thirty-five-year-old’s body.

Getting up from his chair produces a sharp twinge in his ass, and Thor winces. He exhales slowly around the burn of pain and arousal. Just a few feet out of the building, then the parking lot, then up his apartment stairs—twenty feet to the door, and—

Thor licks his dry lips, very much in danger of getting a full on erection in his place of work _and_  a building that happens to be stuffed to the brim with children.

Deep breaths.

And maybe his laptop bag in front of his crotch, just in case.

 

– – – 

 

Thor barely has the door unlocked and opened before a pale hand reaches out and yanks him into the apartment. Loki’s beautiful like this, with his sharp smile and green eyes that always seem to be guarding secrets—even in old jeans and a worn thin shirt, Loki is capable of making Thor’s mouth go dry with desire for him.

Loki pulls him close, his hands tangling in the fabric of Thor’s button-down shirt. “And how was work?” he purrs, those eyes flashing with amusement.

“Funnily enough,” Thor replies, grabbing Loki by the hips and kicking the door closed behind him. His shoes are carelessly toed off and knocked aside. “I was pretty distracted.”

“Oh?” Clever fingers undo Thor’s buttons and Loki guides them back into the living room. “I wonder why?”

Thor catches those teasing lips in a kiss. “You know why.”

“Because my dear brother is a cock hungry slut?” Loki chuckles, low in his throat, dark and thrilling. “Want me to fill you up again?”

Before Thor can answer, Loki’s spun them around and a hand presses on Thor’s back, pushing him towards the couch. Thor tears off his shirt, yanking it off over his head and tossing it wherever. Humming, Loki’s fingers skim the waistband of Thor’s slacks, dipping in just an inch.

“I kept thinking about you,” Thor confesses. He reaches behind and catches one of Loki’s hands to bring around to the front of him—Loki molds to his back, the ever-present sly voice in his left ear, and murmurs a pleased curse when Thor kisses those fingers. “I could barely teach.”

“Oh, dear,” Loki says, voice a deep purr, “Am I to be responsible for the ruination of today’s youth?”

Thor snorts. “Don’t give yourself so much credit.”

Loki nips him on the ear for that, just hard enough to hurt. “I may have been distracted today, as well.” His hand drops to undo Thor’s belt and fly, carelessly brushing over his brother’s cock. Hard and wanting, it has pretty much permanently stained Thor’s underwear over the course of the day. When Thor’s pants are finally undone, Loki presses his palm to it, holding his brother’s cock like it were a treasure.

“Oh?” Thor says, but the noise comes more like a gasp.

“Thinking of this,” Loki murmurs, stroking his hand over the covered shaft. “Thinking of your asshole and how you begged to be plugged this morning. Is my come still in you, brother?”

Thor licks his lips and tugs down his pants, boxers and all. Eager to get his hand on Thor’s naked cock, Loki only helps until it’s freed, then he’s plastered himself to his brother again, tugging at his thick cock with one hand and combing through the smattering of hair on Thor’s abdomen with the other.

“Only one way to find out,” Thor replies. He leans into his brother, feels the soft rub of that old shirt against the skin of his back—when Thor turns his head, Loki kisses him, a rough thing with the press and nip of teeth.

“Indeed. I want to see…” Loki shoves Thor forward a step. “Come on, over the couch. Show me how desperate you are.”

And god, that’s what Thor’s been waiting for _all day._ He drops his trousers and settles on his knees, smirking at the sound Loki makes as he bends over, presenting his ass all scratched around that damn plug.

There’s a rustle of fabric, then the t-shirt’s thrown next to Thor’s face. It’s almost enough to make him turn back around, because Loki’s chest is a sight he’ll never get sick of—just the thought of sucking on one of Loki’s dark nipples is enough to make him bite his lip.

Loki glides his hands down the toned muscles of Thor’s back, his nails catching ever-so-lightly and making Thor shiver. “Look at you. Look how bad you want your brother’s cock.” He kisses the divots right above Thor’s ass, one after the other, his tongue darting out to taste the salt of his skin. “And _this._ ”

Thor groans as Loki runs a finger over the base of the plug, and the sound echoes in the living room.

“What would they say, brother,” Loki’s breath is hot sin in his ear, the words curling like rich wood smoke, “if all your esteemed co-workers could see you now?”

He doesn’t mention Thor’s students, and Thor’s so, so grateful for that, because his world is already shuddering and cracking—what _would_  they do? What would the old librarian say? Or Becca, who teaches English to freshmen right across the hall and flirts shyly with him over lunch?

If they could see him like this, bent over for his own brother, thighs shaking as Loki traces a lazy finger around the plug in Thor’s ass… His rim tightens with each circle.

Thor knows it’s impossible, but he swears he can feel the loads of come inside him—Loki had been randy when they woke up, whispering beautiful, loving filth as he fucked Thor in the watery and pale light of the morning.

The plug had been his own idea, and the look of heady wonder on Loki’s face made Thor wish they were teenagers again.

Loki presses his lips to Thor’s ear, then the pulse-point of his neck, down his shoulder-blades, and over the knobs of his spine.

“Look how wet you are,” Loki praises—he always has, forever dropping charming words like golden coins, well loving the way they make his brother tremble. “Did you think about me today? Hm?” A slender finger presses against Thor’s rim, then pops into his slick hole along side of the plug.

“Yes,” Thor slurs, because of course he did. Every shift, every step, every time he sat, his hole clenched on the unyielding toy. “Brother—Loki, please…”

Loki chuckles. His other hand traces the hard flex of Thor’s abdominals. “Do you need another load? Of course you do, what am I saying… I’m going to stuff you and plug you over and over, brother. If you’re not fat and pregnant by the end of the weekend, I didn’t do my job.”

Thor thinks he might choke; the couch cushion presses into his face, the fabric damp and stained dark with drool. “Loki—”

“Can you even imagine?” His brother whispers reverently. Loki’s thumb strokes the ridges of muscle on Thor’s stomach, tender, and Loki can’t seem to stop kissing the dip of his spine. “Carrying my child? The world would know that you were my cockslut—mine, mine, all mine. Ohhh…” he exhales with a shudder. “I’d make you so much bigger, brother. Let me.”

_Bigger,_  his brother says. But Loki has always loved Thor’s size—ever since they were teenagers and Thor’s biceps began to swell with the casual strength of a young man. Or when Thor worked on his pectorals, just to see Loki’s lips part at the sight of that thick, meaty flesh.

Bigger.

Thor will be bigger for his brother.

Thor arches his back with a grunt—yes, god, _yes_ , and everyone would know his depravity—fucking his own twin brother, his own flesh and blood, his mirror in every way—

Loki eases out the toy and hums in satisfaction. His hole must be so sloppy, so open and wet—a drop slides down his perineum and Thor can’t tell if it’s lube or his brother’s come. Whatever it is, Loki chases it with his tongue, licking a hot stripe behind his balls and buries it back in Thor’s ass.

“ _Fuck…_ ”

There’s a moment where Thor just closes his eyes and enjoys the feeling of his brother’s tongue soothing the raw ache of his spread hole, but it’s here and gone, because Loki pops off, intent on continuing his super-villain monologue. Still, Thor wastes no time in hissing his disapproval. “Loki, you bastard, I swear to god—”

He twists his head around to glare fully at Loki. There’s a thoughtful, intrigued look on his face that bodes ill. Then his mouth, glistening with spit and lube, stretches into a wide, devilish grin. “I wonder how many times I can come in here before you get fat with it?”

Heat pours through Thor; he can just imagine, his belly swollen like he had a few too many beers, only instead of being evidence of a night out with the boys, it’d be because his brother unloaded his balls until they turned to prunes. Thor licks his lips. “I bet you couldn’t,” he says, because nothing riles Loki up more than being told he _can’t._ “I bet you’d be worn out after just one go.”

Loki cocks his head, a tightness coming to his eyes. _Gotcha._  “Do you think so?” he replies. His grin turns a touch crueler—it’s a good look on him. He leans forward to bump his clothed hips into Thor’s ass; a promise of a good, hard fuck. “I have more than enough to satisfy you, brother. But maybe I won’t come in your ass; maybe I’ll just fuck your tits, make you walk around with my spunk under your shirt.”

Thor can tell he’s blushing; there’s heat burning down his neck and his ears go hot. Of course Loki can tell—he can always tell—and his green eyes narrow into pleased, half-moon slits.

The _zzippp!_  of Loki’s fly seems to resonate in Thor’s chest. His belly goes molten; his cock, so hard it leaks onto the nice rug. “But no, brother. I promised to get you pregnant, and I intend to do everything in my power to make that happen.”

Thor’s all open and wet for his brother, and he wiggles his ass a little, stretching back to display himself further. Loki’s belt clinks as he pulls his pants down, his breaths rough and forced. Then he can feel it, the blunt press of his brother’s cockhead, teasing at his messy entrance.

“I should make you beg,” Loki hisses. But he’s impatient—the game is well and good up until this point, and that’s when Loki starts to let himself unravel, so eager to be buried in Thor’s ass.

So Thor just smirks to himself and says, “Can you wait that long?” He pushes back before Loki’s sharp reply comes. He’s so loose that he takes the swollen tip of Loki’s cock with no resistance; it slides in like it was made to fit.

In that moment, Loki’s moan sounds almost worshipful. Loki fucks deeper into Thor’s hole, far harder than he would be able to take if he hadn’t already been stretched from the plug. Loki is near incapable of sweet, slow lovemaking when he’s the one giving the fucking—that’s Thor’s expertise. No, there’s always a barely concealed desperation to Loki’s thrusts, his clinging, scrapping hands, the harshness of his panting as he drives himself into his brother as though he would not be allowed another chance.

“Thor,” Loki gasps, “Thor, Thor, _Thor._ ”

Thor grunts in response, lifting his hips to accept his brother’s fucking—he’s dying from the hunger of it, the burning of his hole igniting the arousal that’s simmered low his his belly all day, since their round that morning when Loki got that devilish glint in his eyes at the sight of the packaged, hot pink plug.

Loki’s moans are more like whines now, high pitched in the back of his throat; his greedy hands palm Thor’s meaty tits, squeezing and pulling at his nipples as if to milk him. “ _Ah!_ ” Thor grits out, a steady stream of _yes_ ’s and _harder_ ’s and _more like that, brother, please_ ’s falling from his lips.

But Thor’s cock is pounding; he’s been forced by the weight of Loki further up onto the couch and his cock is rubbing raw on the fabric. He worms a hand down only intending to rearrange to draw out this good fuck, but the tight grip he gets on himself combined with the pounding into his hole feels too divine to stop.

“That’s it,” Loki says between hard draws of air. “Come on.”

It’s a race now, as it always is—a race of who will come first. Thor jerks himself, eager to squeeze his orgasm out around the thickness of his brother’s cock, and Loki fucks faster if only because he’s driven to win no matter what stupid competition they might be having.

The air around them is thick when their gasps and the smell of sweat. Thor can feel his orgasm tightening in his balls, eager to burst out. He whines, high, and Loki digs his fingers harder into the meat of Thor’s pecs, groping mercilessly.

“These… fucking… tits,” Loki grinds out. “ _Fuck._ ”

“Come on, brother,” Thor says, goading. He flexes his chest muscles and Loki swears and gasps and _comes_  with a loud groan that resonates in Thor’s chest. Loki’s strong hips keep pumping, driving his come deep inside his brother, as though it might truly find a place to take root.

Thor is, by his measure, patient to the point of sainthood as he waits, hard and wanting, for Loki to gingerly slide himself out.

“Ha,” Loki says as a fat drop of seed follows his cock and drips down the back of Thor’s balls. “Maybe that’ll knock you up.”

But for all his gloating, Loki eases himself back a few inches and guides Thor with a hand on his waist as Thor turns over to rest on his calves. His cock bobs in the air. Looking down, Thor can see the marks Loki’s left on him—great red scratches along the ridge of his tits, partially hidden by the spattering of sandy hair that travels down his navel and nuzzles the base of his cock.

Loki purrs at the sight. “You always looked your best freshly fucked.”

Thor hums. “And how do I look after I’ve come?”

“Divine.” Loki slides back between Thor’s open knees and leans over his brother. A smooth, soft hand grips Thor’s cock and Thor groans at it; the other once again finds a hold on his pec, a thumb stroking over one of the scratches. As Loki works his cock, he bends his head down and presses his brow to Thor's—the heat of their breath mingles and Thor’s heart overwhelms at just how intimate this feels.

Thor cups Loki’s neck, keeping him close, always close, because twins should never be apart—his orgasm is coming, building, and Loki’s hand moves faster, like he can sense it, his fist closing tighter. Thor chokes, drawing his brother closer, fusing their mouths together in a kiss that’s artless and clumsy and _perfect_  and Thor’s gone, his abdomen seizing as he pumps out his love for his brother in thick spurts, all over Loki’s hand as he whispers, _“That’s it, that’s it,”_  against Thor’s lips.

“Oh, fuck,” Thor gasps. His head falls back, not quite touching the couch cushion. “Shit, shit, don’t let it get on the carpet—”

“What am I, fourteen?” Loki snorts. “Keep tight then, or you’ll drip.”

Thor clicks his teeth. “What am I, fourteen?” he mimics back.

Loki just narrows his eyes and raises his hand. “I swear I will smear this in your beard.”

“Ew,” Thor huffs. “Go wash your hand, Jesus.”

Rolling his eyes and bitching under his breath, Loki gets up to do just that, though the act of standing brings on a fresh wave of complaints about knees and being old as he makes his way to the connected kitchen to clean up.

Now that the searing throb of his orgasm has faded to a pleasant warmth, Thor can certainly empathize with his brother—his legs are killing him, all bent up the way they are, and Thor unfolds them and clambers to his feet with a hiss.

The tap from the kitchen faucet turns off and Loki reappears with a handful of damp paper towels. “C'mere, old man.”

“I’m ten minutes older than you, brat.”

Loki snorts, but a small, secret smile lifts his lips. “I can’t believe I’m with such an older man,” he teases. “A whole ten minutes. Scandalous.”

Thor reaches for the paper towels—and Loki makes a play at keeping them away until Thor snatches them—“I know. Who knew I’d get saddled with someone so inexperienced?”

_“Inexperienced—”_

With a laugh, Thor pulls Loki closer and kisses him, muffling the insults until Loki, with a very distinct huff, softens his mouth and lets himself being kissed properly. But he can’t ever let Thor feel like he’s won the round, because as soon as Thor pulls away and bumps their noses, Loki grumbles, “Just go wipe my jizz out of your ass,” and pushes Thor off.

Still, Loki follows him to the bathroom, crowding around the sink as he washes off his cock, because everywhere one goes, the other will always follow.

Except, Thor thinks with a touch of bitterness, when it seems like fate wants to keep them apart. Loki might stay for a few days, maybe a week. But as soon as a project at work catches his eye, he’ll fly off back to the other side of the country to return to work and the flat Loki might call home but Thor refuses to acknowledge as such.

“Should we order in?” Thor asks after their post-sex rituals of cleaning have been completed and they’re back sprawled on the couch clad in housepants or, in Loki’s case, a pair of boxers that Thor strongly suspected might’ve been stolen from his underwear drawer. The windows have been opened to air out the scent of sex, and a breeze rolls its merry way into the living room.

Loki gives him A Look. Not a moment latter, the doorbell rings. Loki heaves himself up and answers the door, completely unashamed. “Oh,” Thor hears over the wave of _Jesus fuck Loki why_ , “Well, put them over there, I suppose.”

He steps back to allow a pair of men through, both studiously avoiding eye contact with a nonplussed Thor, and carrying a packed cardboard box each.

“Uh?”

“What?” Loki says. “I told you I was coming to stay.”

“I thought—,” Thor stammers.

“Oh, don’t do that.” Loki reaches over and pats his cheek. “It doesn’t suit you. Now, where should I set up my desk…”

“But you—”

Loki turns to face him, and there’s a moment—just the briefest moment—where Loki’s face is open, vulnerable, like when they were children. But it’s gone in the toss of sleek black hair of a broad and pale shoulder. “I told you,” Loki repeats, slow, like Thor’s an exceptionally dim child, “that I was coming to _stay._ ”

He comes over and reaches a hand to cup Thor’s neck—a gesture that Thor mirrors without thought. Loki’s come home.

“So stop being so fucking stupid, okay?”

“But your work?”

“Funnily enough,” Loki sniffs, crossing his arms over his chest. “it’s pretty easy to find a job as an architect wherever you go. And there’s some bank building a new headquarters downtown that needs designs.”

Thor touches their foreheads. “You’re such a shit. A conniving, scheming shit.”

“Tell me you don’t love my surprises.”

“Mm,” Thor hums. Mindful of the movers still carrying in package after package because apparently Loki needs every single one of his worldly possessions, Thor leans down and presses a soft kiss to Loki’s ear. “I love you, brother.”

Loki’s hand grips his neck a touch tighter; his thumb runs just under Thor’s jaw and he knows Loki is returning the sentiment.

 

* * *

 


End file.
